Brachy therapy has become of increased importance in the treatment of certain diseases, especially cancer, in that the radiotherapy can be administered to very localized human body areas, as opposed to broad beam radiotherapy. To achieve this localized radiotherapy, a radioactive source must be placed in close proximity to the tissue being treated, since the radioactive source effects only low levels of radiation at a significant distance from the source, while high levels of radiation are effected near the source, i.e. the application of the inverse square of the distance law. The application of the radiotherapy is normally achieved by guiding a radioactive source through at least one guide member, e.g. a position member or a tubular guide, until that source reaches the site of the tissue to be treated, e.g, cancerous tissue. A regimen of radiation is then administered according to a program defined for the particular cancerous tissue and that therapy is, usually, periodically repeated until effective control of the cancerous tissue is achieved.
However, since radiation is involved in the therapy, technicians who routinely administer the therapy to a number of patients would be unduly exposed to radiation in the conduct of those therapies if the technician were in close proximity to the patient being treated. To avoid such radiation hazard to the technician, apparatus has been developed for allowing the radiation source to be moved to the site of the radiotherapy while the technician is not in close proximity to the patients being treated, e.g. is not in the treatment room where the patient is being treated. Such apparatus is known in the art as remote afterloading apparatus for brachy therapy. When using such apparatus, a physician places a positioning member, e.g. a needle or canula, at the site where radiotherapy is to be effected. This positioning member in some applications may be attached to one end of a tubular guide and the tubular guide is attached at the other end thereof to a connection head of the remote afterloading apparatus. After such positioning and connections are made, a technician, from a remote location, e.g. another room, can cause the apparatus to drive a cable with a radioactive source attached thereto from a "safe", through the remote after-loading apparatus, the guide member, e.g. tubular guide, and into the positioning member for radiotherapy. Thus, a technician will not be in close proximity to the patients, e.g. will be in another room, while the radioactive source is out of the "safe" and while administering the therapy.
While apparatus of the above nature has been used for some time, a particular problem in connection therewith has been the adaptors for connecting the guide member, e.g. tubular guide, and/or the positioning member to the connection head of the remote after-loading apparatus or attaching the one to the other. For example, since the cable, with the radioactive source, must slide through the tubular guide, and the tubular guide is quite small, any kinking, compressed configuration, or the like of the flexible plastic tubular guide, caused by the adaptor, can cause the cable moving the radioactive source to bind therein, which results in a failure of moving the radioactive source to the correct site for effective radiotherapy. Thus, the adaptors have been a constant problem in the art. In addition, once the positioning member is in place in the patient, it is important to quickly and effectively connect the tubular guide to the positioning member or the positioning member to the connection head so as to minimize delay and discomfort to the patient.
In the past, such adaptors have taken the general form of metal tubes and the tubular guide or positioning member is slid (partially forced) thereover. However, in view of the very small diameters of the flexible, plastic tubular guides or positioning members, the time required for so attaching the same to a metal tube is inordinately long and in addition, distortion during attachment can cause uneven compression of the flexible, plastic tubular guide or positioning member which will result in the kinking, binding and the like of the cable with the radioactive source attached thereto. Thus, it would be of substantial advantage to the art to provide improved adaptors for connecting the tubular guide or positioning member to the connection head or to each other wherein the adaptors allow for quick and easy connections without the necessity of fitting to a metal tube or any other laborious attachments, such as screwing or unscrewing devises, and where such connections avoiding distortion or compression of the tubular guide or positioning member so as to avoid the kinking, binding and the like by the cable.